Attention-deficit/hyperactivity disorder (ADHD) has an impact on the family as well as the affected child. This study developed and tested an electronic diary for mapping the challenges of everyday family life in a sample of children with ADHD being treated with pharmacotherapy. Across 7 days, mothers and children (27 ADHD; 25 non-ADHD) independently reported their moods, behaviors, and social contexts every 30 min during nonschool hours. Symptomatic behaviors and negative moods were elevated in the ADHD group, combined with maternal perceptions of lower parenting effectiveness and quality of life. Differences in the contexts of maternal anger were salient, with mothers in the ADHD group more often angry when with their children and comparison mothers more often angry when not. Although mothers' diaries were more informative, children's diaries also distinguished the two groups, especially during mornings and weekends. The need for family-wide interventions, the utility of child self-reports, and the promise of electronic diaries are discussed.